Mercurio-electric fire-alarm.



APPLIGATION FILED MAILB, 1912.

Patented June 23, 1914.

WITNESSES Wow COLUMBIA PLANOGRAPH C0,. WASHINGTON. n. c.

UNITE LYON CAVALIER, OF WEST MAITLAND, NEW SOUTH WALES, AUSTRALIA.

MERCUBIO-ELECTRIC FIRE-ALARM.

To all whom it may concern Be it known that I, LYON CA"ALIER, subject of the Ottoman Empire, and residing at High street, Vest Maitland, in the State of New South Vales, Commonwealth of Australia, have invented new and useful Improvements in Improved Mercurio-Electric Fire-Alarms, of which the following is a specification.

The apparatus that forms the subject of the present invention is intended to give warning of an outbreak of fire in the premises where it is installed, by causing an electric bell to ring, when there is an abnormal rise in temperature due to combustion.

The invention comprises a bent tube, of the same kind as is seen in a mercury barometer but open at the top of the long leg, while the short leg terminates in a bulb containing atmospheric air at normal pressure. Traversing the bulb, entering the short leg of the tube and passing more than half way around the bend of the tube is the terminal wire of one pole of an electric cell. The bend of the tube will be filled with mercury so that the end of the terminal wire will be immersed in the quicksilver. Projecting down the long leg of the tube is the end of the terminal wire of the other pole of the cell, This terminal wire is attached to the bottom of a small bucket that will be filled with mercury; the bucket suspended from the wire may be raised or lowered as desired. The end of the terminal wire will be immersed in a mercury bucket. The bucket may be connected to a tube adapted to slide up and down in the long leg of the tube, but perforations must be made in the sliding tube so as to admit the mercury that lies in the bend of the tube when it rises in the long leg owing to a rise in temperature. A scale may be engraved upon the sliding tube so that the position of the bucket within the tube may be readily ascertained, if the appliance be inclosed in an opaque casing,

In the accompanying drawing Figure 1 shows the appliance in vertical section and Fig. 2 is a detailed sectional view showing a modification of the device. In Fig. 1 temperature is assumed to be normal,

Specification of Letters Patent.

Application filed March 8, 1912.

Patented June 23, 1914.

Serial No. 682,408.

A, A are the long and short legs, respectively, of the main tube. 13 is the bend between the same, C is the bulb that closes the top of the short leg A the same being full of atmospheric air at normal pressure.

D is the terminal wire from one pole of an electric cell. The wire D extends to the A side of the bend B and will be immersed in the mercury E that lies in the bend. Inserted into the top of the long end is a terminal wire F from the other pole of the electric cell. This terminal wire F is secured to the bottom of a bucket G, (that must be filled with mercury, as shown in the draw-- ing) so that the bucket G shall be suspended from wire F. It is important that the position of the bucket G within the tube A should be susceptible of adjustment, there fore, the bucket G may be either an extension of a sliding tube H (as shown in the drawing) with perforations 7 to admit mercury from without or it should be cut short at a point, such as h, and the basket be suspended solely fromthe terminal wire F.

The apparatus will operate in the following manner, viz: When the temperature rises, in the vicinity of the appliance, the air in the bulb C will expand, thus forcing the mercury E up the long leg of the bent tube until it overflows the bucket G when the electric circuit will be complete and the warning bell will ring. It has been found that the bulb C is indispensable to insure a speedy response of the mercury to a circumambient rise in temperature. It has also been found to be indispensable that the ends of the terminal wires I), F be immersed in mercury so as to minimize or neutralize the danger incidental to oxidation of the surfaces of the terminal wires. While the ends of the terminal wires are immersed in a mercury bath there can be no oxidation that will affect the completion of the electric circuit.

I claim In apparatus of the class described, in combination, a bent tube, mercury positioned in the bend thereof, an air bulb at one end of the tube, a terminal wire extending through the air bulb and having its end immersed in the mercury, a second terminal name to this specification in the presence of two subscribing Witnesses.

LYON CAVALIER. Vitnesses PETER S. HAINEs, E. W. PA'roN.

Copies of this patent may be obtained for live cents each, by addressing the Commissioner of Pate uts,

Washington, D. C. 

